A student boy becomes embroiled in the murder of a teacher's wife.
Inspector Cameron doubts a suicide linked to a church choir.
Cameron investigates a diamond robbery. The Great Detective is confronted with the mystery of a stolen diamond and a set of missing twins. Inspector Cameron is called in to investigate the disappearance of Queen Victoria's famous Star of Bengal diamond. The case becomes complicated with a second disappearance — a set of Siamese twins.
Inspector Cameron investigates the murder of a young military cadet killed on his wedding day.
The young heir of an affluent family is killed by a chambermaid.
Dr. Chisholm provides an important link to a murder.